The glock 17 airsoft co2 powered handgun is a full blowback 6mm pistol! fully licensed by umarex this glock has all the features of the firearm, but in a 6mm airsoft version.This is the gen 4 edition of the full frame glock 17.It uses standard 12-gram co2 cartridges that insert into the magazine that holds 23 rounds.This glock 17 gen4 has a fully adjustable airsoft ho-pup system and fits most if not all standard glock 17 holsters, accessories, and gear.Caliber: 6mmCapacity: 23rdSights: Fixed